Why do you think the story gives such specific details about the setting–the time and place of the story? in the lottery by Sherley Jackson

Shirley Jackson really wants to play up the irony in her story. The setting is a small, nondescript town with a population of approximately three hundred people. On a clear morning, June 27th, the townspeople, starting with the children, begin to assemble for the lottery to begin at ten in the morning. It would seem the setting for a tranquil rural town somewhere in America. Jackson is able to juxtapose this setting with a far more sinister subtext.